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1.
The status of single-case designs in counseling psychology is reviewed. Also, reasons for the underuse of these designs by counseling psychologists are discussed. Finally, potential contributions (1) in research linking process and outcome, (2) in group counseling, (3) across a variety of theoretical approaches, and (4) to evaluation and quality assurance in clinical practice are described. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Rheological Property and Stress Development during Drying of Tape-Cast Ceramic Layers 总被引:1,自引:0,他引:1
Jennifer A. Lewis Kimberly A. Blackman rea L. Ogden James A. Payne Lorraine F. Francis 《Journal of the American Ceramic Society》1996,79(12):3225-3234
Rheological property and stress development of tape-cast ceramic layers derived from nonaqueous alumina (A12 O3 )-poly(vinyl butyral) (PVB) suspensions were observed during drying. Casting suspensions exhibited strong shear-thinning behavior, with a low shear Newtonian plateau apparent viscosity >102 Pa. s. The apparent suspension viscosity displayed a power-law dependence on the A12 O3 volume fraction during the initial stage of drying (<30% solvent loss). Stress development, measured by a cantilever deflection method, and parallel weight loss measurements were performed during the drying of tape-cast layers and pure binder coatings. Maximum drying stresses (σmax ) of 1.37-0.77 MPa were observed for plasticized tapes cast at gap heights of 150-400 μm. In contrast, nonplasticized tapes of similar thickness displayed a more gradual stress increase, with σmax values approximately an order of magnitude higher than their plasticized counterparts. The stress histories of the corresponding binder coatings were quite similar to the tape-cast layers, albeit slightly lower σ max values were observed. Stresses decayed beyond σmax with a logarithmic time dependence to an almost constant value of 0.2-0.4 MPa for the plasticized tapes. Based on these observations, process methodologies have been offered to minimize stress development and retention in tape-cast ceramic layers 相似文献
3.
The modern fruit juice industry needs their products to be characterized by high-quality attributes to meet consumers’ expectation. In this view, the composition of 26 Italian commercial apricot juices obtained from organic, integrated and conventional agriculture was analysed for carbohydrates, organic acids, amino acids, phenolic compounds and furanic compounds by high-performance liquid chromatography (HPLC). The content of 5-hydroxymethylfurfural in apricot juices (range 0.1–18 mg/l) was within the regulatory limit of 20 mg/l. The lack of furanic compounds in apricot fresh fruits confirmed their importance as quality markers of heating condition during processing and storage of fruit juices. Univariate analysis disclosed some significant differences among the composition of the apricot juices in terms of glucose, fructose, malic acid, glycine, chlorogenic acid, rutin, and a∗-parameter (redness). Principal component analysis on chemical composition of apricot juices resulted in two principal components (PCs) that accounted for 66% of the total variance. Organic apricot juices showed some separation from the other juices, whereas a lack of distinction between integrated and conventional juices appeared. 相似文献
4.
Persistent, bioaccumulative and toxic substances in fish: human health considerations 总被引:3,自引:0,他引:3
Dórea JG 《The Science of the total environment》2008,400(1-3):93-114
Fish are important dietary items that provide essential nutrients. Fish however, bioaccumulate monomethyl mercury (MMHg) and organo-halogenated pollutants (OHP) that are persistent bioaccumulative and toxic substances (PBTS). Unlike man-made OHP, MMHg is mainly of natural origin but background concentrations of aquatic systems are determined by the environmental Hg-methylating potential. Industrial activities can modulate environmental discharges and fish bioaccumulation of PBTS. Fish and seafood consumption are associated with human body load of PBTS, but farming practices that utilize fishmeal increase the terrestrial food chain resulting in farm-animal accumulation of PBTS. These substances are neurotoxic and endocrine active that can impact humans and wild life, but chemical characteristics of MMHg and OHP modulate interactions with animal tissues. MMHg is protein reactive with a faster metabolism (months) than OHP that are stored and slowly (years) metabolized in fat tissues. Except for brain-Hg, neither Hg nor OHP in tissues are markers of toxic effects; however, deficits in neurobehavioral test-scores of children have been shown in some fish-eating populations. These deficits are transient and within normal range, and are not prodromes of neurological diseases. Although population studies show that consumption of fish at current levels of contamination do not explain neurological disorders, endocrine activity remains controversial. Understanding risk of hazard caused by fish-PBTS consumption requires a wide range of expertise. We discuss chemical, toxic, metabolic, and ecological characteristics associated with PBTS in fish. There are proven health outcome derived from fish consumption, while risk of exposure to avoidable PBTS is a chance that can be minimized by societal actions. 相似文献
5.
Trace metals, PCB congeners and DDT homologues were determined in composite sediment samples collected from 10 representative sites along the river Po in two separate seasons. The aim was to identify the most anthropogenically impacted areas for future monitoring programmes and to aid development of Italian sediment quality criteria. The surface samples were collected during low flow conditions. Trace metal concentrations were assayed by electrothermal (Cd, Co, Cr, Cu, Ni, Pb), flame (Fe, Mn, Zn) or hydride generation (As) atomic absorption spectrometry after microwave assisted acid digestion. Hg was determined on solid samples by automated analyser. Organic microcontaminants were determined by gas-chromatography with 63Ni electron capture detector after Soxhlet extraction. Concentrations of trace metals, total PCB and DDT homologues showed two distinct peaks at the sites immediately downstream of Turin and Milan, respectively, and in each case decreased progressively further downstream. Principal component analysis identified three major factors (from a multi-dimensional space of 35 variables) which explained 85-90% of the total observed variance. The first and second factors corresponded to anthropogenic inputs and geological factors on sediment quality; the third included seasonal processes of minor importance. Sediment quality assessment identified Cd, Cu, Hg, Pb, Zn and organic microcontaminants as posing the most serious threats to river sediment quality. A reference site within the Po basin provided useful background values. Moderate pollution by organochlorine compounds was ascribed both to local sources and to atmospheric deposition. 相似文献
6.
C Bulletti C Flamigni V Polli E Giacomucci A Albonetti V Negrini A Galassi AM Morselli-Labate 《Canadian Metallurgical Quarterly》1996,3(4):495-501
STUDY OBJECTIVE: To establish the crude effects of danazol and gonadotropin-releasing hormone (GnRH) analogs in the management of endometriosis. DESIGN: Prospective case-control study. SETTING: Unit of the Pathophysiology of Reproduction outpatient department. PATIENTS: Two groups of 110 women each with endometriosis (American Fertility Society score 1-3) who received danazol and GnRH analogs, and a control group who did not receive any drugs. INTERVENTIONS: Women in the treatment groups received danazol 200 mg every 8 hours for 6 months, or a different GnRH agonist at standard dosages for 6 months. Laparoscopy was performed twice, at the time of diagnosis and just before the end of treatment (or no therapy for controls). Surgical treatment of the implants was performed at the second laparoscopy. MEASUREMENTS AND MAIN RESULTS: Samples of both eutopic and ectopic endometrium were collected during both laparoscopies. Both danazol and GnRH agonists were useful in reducing the AFS scores to inactive endometriotic implants, and there were no significant differences between the effects (p <0.001). Fibrosis was found after 6 months of observation in the implants in one control woman (0.9%), in 20 patients (18.2%) treated with danazol (p <0.001 vs controls), and in 4 patients (3.6%) treated with GnRH agonists (NS vs controls). A correlation between a clinical diagnosis of AFS score zero and histologic features of fibrosis in the ectopic specimens after therapies was observed in 28% of women, with poor agreement (k = 0.07). CONCLUSIONS: Fibrosis, which represent the absence of endometrial cells within the specimens of endometriotic lesions or eutopic endometrium, did not appear in eutopic endometria but it was found in some endometriotic implants. Danazol and GnRH agonists reduced the clinical AFS scores of endometriosis, but their histologic effects in completely and permanently eliminating endometriotic implants were unacceptable. 相似文献
7.
Explored the validity of the College Self-Expression Scale (CSES) in the context of 3 alternative models of behavior: personism, situationalism, and interactionalism. 72 high- and 72 low-assertive female college students role-played scenes requiring assertive behavior. The scenes varied on 3 situational dimensions: positive–negative assertion, male–female, and familiar–unfamiliar partner. The dependent measures were content, appropriateness of affect, and duration of reply. Results support the concurrent validity of the CSES and the role of both person and situational, but not interactional, influences on assertion. Implications for assertion training, for using the CSES, and for concept-utilizing assertive behavior are discussed. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Characterization of hot-pressed silicon nitride-based materials by microhardness measurements 总被引:2,自引:0,他引:2
The microhardness A Si3N4-based materials may be related to their phase and chemical compositions and to microstructural parameters such as porosity, grain size and secondary phases. By reducing the amount of intergranular phase, the microhardness may reach values up toHV
500 = 3000 kg mm–2. Moreover, a comparison among different materials must include the microhardness tests in a wide range of values of the applied load. The relationd
n
=B
1 +B
2
d
2, obtained from those of Meyer and Kick, gives two constants:B
1 may represent one class of materials andB
2 is specific for each single material. 相似文献
9.
Marin Cernea Adrian Manea Daniele Piazza Carmen Galassi Eugeniu Vasile 《Journal of the American Ceramic Society》2007,90(6):1728-1732
Fine-grain BaTi0.87 Sn0.13 O3 (BTS13 ) powder was synthesized from an oxalate precursor and used to prepare sintered ferroelectric BTS13 ceramics. The evolution of the morphology and structure of a BTS13 precipitate precursor as a function of temperature was analyzed. We compare the sintering behavior as well as the dielectric properties of the BTS13 ceramics obtained using uniaxial and cold isostatic pressing. 相似文献
10.